DESCRIPTION: (Applicant's Abstract) This application proposes to build upon two previously funded research projects on a sample of over 300 children assessed during grades 2-5 in elementary school and again in grades 9-10 in high school. The overall goal is to study the likelihood of multiple pathways to substance use onset within a developmentally relevant context, to identify distal "causal" behaviors that are potential targets for prevention efforts. In Study 1, the investigators conducted multimethod and multiagent assessments of the children s social status, social relationships, and school adjustment with direct observations of the children on the playground and in the classroom, peer ratings and sociometric nominations, and teacher ratings of social and academic adjustment. Study 2 was designed to follow up these children as they entered high school to assess the predictability of the Study 1 assessments on a variety of adjustment indices, including substance use, delinquency, depression and various indicators of social and familial adjustment. The three major aims of the study are to: a) develop models of childhood, school-based, social behaviors to predict early onset drug use in adolescence and related constellations of problematic behaviors; b) to follow up the sample during young adulthood, collecting data on substance use/abuse and other forms of adjustment, to determine the relevance of both sets of data to predict the late onset of drug use. The follow-up design will allow for the examination of the developmental trajectories of several key groups in terms of drug use/abuse: 1) abstainers throughout the developmental periods, 2) early onset experimenters who quit prior to late adolescence/young adulthood, 3) late adolescence/young adulthood onset, and 4) chronic users. The third aim of the study is c) to examine the consequences of the two stages of substance use onset and its maintenance on a variety of adjustment variables during young adulthood. They will also determine whether substance use onset adds to the power of the school-based social variables to predict consequent events usually associated with drug use and abuse.